<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <div id="app">
        <h1>{{ msg }}</h1>
    </div>
<script src="https://cdn.jsdelivr.net/npm/vue"></script>
<script>
    var vm = new Vue({
        // el: "选择器",
        el: "#app",
        data: {
            msg: "vue.js起步!"
        },
    })
</script>
</body>
</html>